Many different types of sighting systems are known in the art and are used to assist in the aiming of a variety of devices, typically those used to launch projectiles, such as firearms and bows, although they are used in other applications as well. Perhaps the simplest and most rugged type of sighting system is the so-called “iron sight,” which refers to the open, unmagnified aiming system typically used on firearms. An iron sight usually comprises a front sight and a rear sight. The front sight may take the form of a post, bead, or ring-shaped structure, whereas the rear sight may take the form of a notch or aperture. The rear sight is often made adjustable to allow a user to more easily compensate for wind or elevation, although in some applications the front sight is also adjustable.
Iron sights work by providing horizontal and vertical reference points that allow the user to align the weapon with the intended target. Once the front and rear sights are aligned with one another, they are placed in correct relation to the target. However, since the human eye is only capable of focusing at one distance at any given time, it is not possible for a user to focus simultaneously on the front sight and the target. As a result, the aiming process is degraded. That is, the user must first focus on the front sight in order to align the front and rear sights. The user must then re-focus on the target and then place the now out of focus front sight on the target. Because the front sight is out of focus, it is difficult to place the front sight at the precise position in relation to the target to produce a hit.
While telescopic sights represent an improvement over iron sights in that the target and reticle are simultaneously focused for the user, telescopic sights are expensive, heavy, relatively bulky, and easily subject to damage and/or misalignment due to rough handling. As a result, telescopic sights are typically limited to applications where cost and weight are not significant issues and where proper care can be exercised to avoid damage and/or misalignment.